Operating mechanism for automatic stokers



E. B. BRYANT.

OPERATING MECHANISM FOR AUTOMATIC sToKERs.

APPLICATION FILED .JULY Il, 1319.

L41@ 'Patented May I6, N22i.

3 SHEETS-SHEET 2.

E.BA. BRYANT. -OPERATING MECHANISM FOR AUTOMATIC STOKERS.

APPLICATION FILED JULY 11,!919A .Patented May 16, 1922.

teuren stares earenrwoanca.

EVERETT B. BRYANT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGN'OR T0 AMERICAN ENGINEERING COIIIPANY,4 OF'II-IILADELPHIA, PENNSYLVANIA, A CORPORATION or rnivbisvnvema.

OPERATING MECHANISM FOR l.AUTO:tmf-LUCIO STOKERS.

Laisser.

Specification of Letters Patent.

Application leduly 11, 1919. 'Seria1`No.-3`10,237.

To all whom z'tmay concern:

Be it known that I, EmiznrrrB. BRYANT, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented Operating Mechanism forAutomatic Stok-v ers. of which the followingisa specification. ne object of my invention is-to provide l templating a novel combination of mechanical movement and reciprocable ram for each ofthe retorts whereby the'fuel'enteringv the ram chambe-rwill be 'delivered therefrom to 'its retort at a substantially uniform rate and with the necessary force and certainty of action.

It is further desired to provide an automaticfstoker including aplurality of re" torts, with novel mechanism'including devices for feeding fuel thereto whereby any or all of the retort-feeding devices may be' quickly a'ndconveniently disconnected from the main driving mechanism at the will of the operator with a view tol allowing accurate regulation of the amount of fuel delivered to the stoker.

Another object of the inventionris to provide relatively simple means whereby the.

fuel feeding mechanism of any one or more of the lretorts will Abe` automaticallydisconnected from the main driving mechanism `in case of 'said feeding mechanism becoming choked vorderanged;the yapparatus being constructedv t'o permit of the operation'of one ,or Ymore of saiddevices without affecting the action of the others. f

These objects and other advantageous ends! I attain as hereinafterd set forth, reference bein had to the accompanying dra-wings, in-w ich, I

Fig. -1 is 'a vertical longitudinal section of afurnace having applied to it an inclined underfeed stoker equipped Withmy vinven- Fig. 2 is alhorizontazl section partly on the line 2 2, Fig. 1, further illustrating myscale, further illustrating my invention;

Fig. 4C is a vertical section onthe line Ll---Ll, F ig- 3;

Figs.. 5 and 6 are fragmentary vertical sections, illustrating details of my inventi'on, and.

Figs. 7 and 8 are respectively a longitudinal section anda vtransverse vertical section coasting parts. Y

In the above drawings 1 represents the setting of a boller furnace having a bridge wall Sand provided with a ram chamber 4.

supported on a plate structure 2 at the frontv of the setting. The ram chamber structure not only supports 'the hoppers 5 but is also provided with projecting brackets 6, 7, 8 and 9 'of which the firstfthree support bearings for the main driving shaft 10; This'shaft under operating conditions is constantlyv driven from a sultable source ofpowersuch as a sprocketc'hain lt() or equivalent structure 'through a wheel l2 fixed Vto-,said shaft.'A

- In Ythe present ,instance I. have|"shown a Patented May is, ieee.'

lillustrating the swivel nut and cer-tain of its Stoker providedwith twozretort-sfl1f1and 14 u each having .connected toit onefo'vfv1 the/fram chambers 4 and in each of' these'vlatte'r is op*- erative a #recipro'cable ra'rnj'l"preferably e having the forinfo'f a cylinder? 'lhs is held from rotating by. a setA 'screw "or bolt 4,1.6

threaded intothe bottom. of the ram chainber andfprojecting into `a`` longitudinally extending groove orlkey-way 17 in the ram.-

F or reciprocatingl the rams from the driving shaft 10, I"n`1ou'nt`--on" the. forward or outer end of eachpof thema plate 18 having an elongated opening through which a diamond screw 19 is longitudinally movable. Said screw consists of a. shaft or spindle provided with 4two oppositely. inclined intersecting gli' helical grooves constituting right and left' hand threads joined or running together at their',4 ends, This screw is engaged by a swivel nut' orequivalent. device 20 carried by the plate 18l and' is connected through a coupling 21 with a short shaft 22 to whose forward end is fixed a flangedcollar 23, the bracketQproviding a bearing for lsaid shaft and the coupling and collar cooperating y with the yends of this bearing respectively -to take the opposite longitudinal thrustsof the .diamond screw 19.-

Loosely mounted on thecollar 23 is a bevelled gear 24- operativel connectedto Iit by a shearing pin 25 extench7 ng into orI lying.

within a pain of hardened steel bushings'26 and '27 respectively mounted in the collar and in the gear. The'teeth' of this gear en gage a bevelled pinion 28 loosely mounted on the shaft 10 and having lformed integral with 'itfone part 29 Vof a' jaw clutch, -the sec# ond part 30 of whichis keyed to said shaft, An-operating lever 31 is suitably connected to this second clutch member so as to be ca pable of longitudinally moving it upon the shaft into and out of engagement wlth the clutch member 29.

f The Stoker includes tuyere blocks 3 2 mounted on a'tuyere box 33 below which is supported the wlnd1 box or air supply conduit` 34. The inner' or lower end of .the tuyere box is supported on an auxiliary air box 35'for supplying the extension grate 38 and the latter with its actuating mechanism is carried upon beams 36 and-37 supported on or forming part of the main frame structure of the stoker. Between said extension grate and the bridge wall 3 is mountedthe dumping plate 39 whereby the ashes accumulating in thetransverse pocket adjacent said bridge wall, may be periodically dumped.'

Said plate is normally maintained in the position shown andl isoperable at will by suitable means constituting no part of the present invention. v

. Under conditions of operation the driving shaft 10 is continuously rotated in one direcf tion by power from a suitable source,v con-l nected through the chain 50 with the' sprocket wheel I12, and vif both of theclutches 29-30 be lthrown in so that power is trans.

fmitted to the bevelled pinions 28,`the two diamond screws 19 are continuously turned;

the construction ofl the groove of each of 40 thembing such thatthrough the swivel nut 20` the rams -15 are moved alternately back and forth within their respective ram chambers. This action is dueto thefact that `saidnut follows the thread of the screw and is free to oscillate in' itssupp'orting structure 18 when, on reaching either end of said screw, its direction of motion is re -versed by said thread. As a consequence,

. the continuous rotation' of -the diamond` l screw in one direction causes a reciprocating movement ofthe nutand of the' ram associ l'atedtherewithl j The forward movement'of each-ram--per-- mits fuel to fall from 'the hopper 151v into the rear part of the ram chamberand the subsequent rearward movement of said ram -.forces said fuel into the adjacent retort andv -thence into the furnace where itgis burnt with the air supplied from the wind boxes 6o 34.- and 35 through the tuyere blocks 32 and the extension grate 38.l

' .By the use of the .diamond screw it will` be. noted. that the ram associated therewith is forced rearwardly with each charge of fuelfat a uniform and constant speed andis 65 automatically movedl forward after having reached the limit of its rearward movement, so that the fuel is delivered at the desired rate and in .such manner that likelihood of the ram sticking or becoming cloggedis re. duced to a minimum.

If for any reason either of the rams should encounter some obstacle which would interfere with its movement, the abnormal stress on the driving mechanism would cause shearing' of its pin 25, thereby automatically disconnecting the shaft 22 from the bevelled gear 24 which actuates it, and preventing' damage tothe mechanism or its associated. parts.

If for any reason it should be advisable or necessaryv to vary the rate of feed of the fuel -to the furnace or to altogether stop it fora time, this end ma be easily accomplished without interfermg with the' oper-v ation of the driving mechanism by operating either or both of the clutches 29-30 so as to stop feeding by either or both of the rams. When. desired either or both rams may again be put in action.

1. The combination in an inclined underfeed s toker of a retort; a ram chamber connected thereto and communicating therewith; a ram in said-chamber; a removable plate securedto the vforward head of said ram andformed with an elongated-bearing therein; a diamond screw operative in the bearing; a nut mounted in said plate, having a portion projecting'into the bearing in en- 10() gagement with the diamond screw and free to oscillate to permit it to follow the thread thereof at its ends to cause reversal ofthe movement of the platev and ram; means for preventing rotation of the ram under the action of the screw; and means for rotating the screw to cause it to reciprocate the ram through the nut and plate.

. 2. he combination 1n an underfeed Stoker l of a retort; a ram chamberconnected there- -to and communicating therewith; a i ram in said chamber; a bearing on said ram; 'a diamondl screw operative'in the bearing; a swivel nut mounted in said bearing. with a -portionprojecting into and in 'engagement with the diamond screw and free to oscillate threads of said screw; means at vthe ends of the screw tof cause reversal 'of the direction of movement of the bearing andram; and means for rotating the screw tocause itto reciprocatevthe ram through thel agency of thelnut. In witness whereof l aiix my signature.

avsnn'rr B. BaYAN'r. 

